Temporary rough idle when cold

[gchristofi]

Hello guys. I've been having this issue since this cold season began. First minute or so of engine running from cold and the idle becomes very rough (will judder if in gear) and the CEL flashes. After a short while all disappears and everything appears normal. Doesn't do it if there is any warmth in the engine i.e. run in last 5-6 hours. Has occasionally stored a Multiple misfires code but not always.

I thought this post on xoutpost regarding valvetronic intermediate levers was interesting (wish I knew exactly how they worked).

http://www.xoutpost.com/bmw-sav-forums/ ... ays-2.html

Question is, anyone else having similar issue and done anything to resolve it. I reckon I can live with it if it's not doing any long term harm.

[Rick]

I had same problem,i take it you have a V8,when i started car on very cold mornings i would get a missfire and within 1 minute everything would be fine
The problem was wear on the valvetronic levers,i had these replaced and car was fine luckily under warranty.

[Turks]

Mine does the same, I have been meaning to get it booked in to have the Valvetronic Levers done. It shudders like it is almost about to stall when in gear. I should have this done before my Warranty expires.


Turks.

[CondorX5]

I've noticed this on occasion as well......its a pretty poor show, though, if valvetronic levers have to be replaced in a car thats only done 34000 miles!!! Must book it in likewise as there is the old intermittent PDC blip as well.....

[Lee4.8is]

I also suffer with this problem aswell...its hard to understand how this engine won international engine of the year once upon a time!!

It does shudder the whole car when in gear & also feels like it could stall but as soon as you drive off its fine.

At least its a common fault because i was worried at first.

[gchristofi]

[quote=""Rick""]I had same problem,i take it you have a V8,when i started car on very cold mornings i would get a missfire and within 1 minute everything would be fine
The problem was wear on the valvetronic levers,i had these replaced and car was fine luckily under warranty.[/quote]

Sorry, should have mentioned, my car is 2004 4.4 with approx 65k miles.

Do you guys know how expensive a job this is (I don't have a warranty) and whether it can cause bigger issues if left as is? I can handle 60 seconds of idling before moving off no probs but don't want to ruin anything.

[Turks]

[quote=""Rick""]I had same problem,i take it you have a V8,when i started car on very cold mornings i would get a missfire and within 1 minute everything would be fine
The problem was wear on the valvetronic levers,i had these replaced and car was fine luckily under warranty.[/quote]

How did you go about this Rick? Did you just take it in and get them to diagnose or did you tell them what you thought it was?

I don't want to take mine in and get fobbed off for one reason or another. It would be impossible for them to replicate the problem with out the right conditions outside. Need this to be done before the beautiful warranty runs out!


Turks.

[Turks]

[quote=""gchristofi""]Do you guys know how expensive a job this is (I don't have a warranty) and whether it can cause bigger issues if left as is? I can handle 60 seconds of idling before moving off no probs but don't want to ruin anything.[/quote]

I'm not sure on the cost but I imagine it won't be too cheap. I'm not sure if this should have been a recall or not? I seem to remember reading something to that effect.

I don't think you will have any problems with it running rough for start up. I just don't drive off when it does this now, just give some revs to get the warmth in the parts - maybe should just let it warm itself up?!


Turks.

[gchristofi]

[quote=""Turks""][quote=""gchristofi""]Do you guys know how expensive a job this is (I don't have a warranty) and whether it can cause bigger issues if left as is? I can handle 60 seconds of idling before moving off no probs but don't want to ruin anything.[/quote]

I'm not sure on the cost but I imagine it won't be too cheap. I'm not sure if this should have been a recall or not? I seem to remember reading something to that effect.

I don't think you will have any problems with it running rough for start up. I just don't drive off when it does this now, just give some revs to get the warmth in the parts - maybe should just let it warm itself up?!


Turks.[/quote]

I am using the same approach as you, don't move until the engine settles down to a smooth(er) running. BTW, do you get an unusually high smell of unburnt fuel during this time?

Since I don't have a warranty I'd also like to know if something else might cause this problem such as split breathers or idle control valve (is there one?).... always worth clutching at straws before accepting the truth...

[Turks]

Coil Packs could be causing the rough idle but then that would cause a misfire for longer than what we have mentioned. What year is your car?


Turks.

[gchristofi]

[quote=""Turks""]Coil Packs could be causing the rough idle but then that would cause a misfire for longer than what we have mentioned. What year is your car?


Turks.[/quote]

it's an 04 plate. True re: the coil packs and you're right, even an intermittent issue with those would be likely to rear its head at other times not just on starts from completely cold engine.

[Turks]

IIRC Nat_h posted on here some time ago about the Valvetronic Levers. I think in there it said something about the problem being on 04 V8's over a couple of months (can't remember when although August to November springs to mind) having Levers that were manufactured out of tolerance.

I'll have a search and get back... it could have been on old forum.


Turks.

[Rick]

I left my x at the dealers for about a week as the fault would not always occur unless temp got below 0,they fired the x up and there was a miss fire on 3 cylinders.I do think if it was only on 1 cylinder you may not notice it,car was under warranty and they only wanted to replace the levers on the 3 cylinders,now whats the point in that,kicked up a fuss and they finally agreed to do the whloe lot
Took 2 days for repair,was told approx cost would be close to £2000

[gchristofi]

Thanks guys. @Rick, £2000 actually seems quite reasonable considering the scope of the work..... not that I fancy paying that if something else is at fault or i can safely warm up for a minute and ignore the prob.

[alanva]

My 06 4.4i ( 35k miles) had the rough idle in very cold weather. Mine was out of BMW warranty by the time I experienced this as the weather obviously hadn't been cold enough previously. The dealer checked the codes ( CES light had flashed) and decided to replace 4 of the ignition coils. It didn't cure the problem. I then made them aware of the Intermediate Lever issue (there was a Service Bulletin issued by BMW USA but NOT a recall) - they checked the levers & said they were responsible for the rough idle but "within BMW's tolerance" ! I wrote (nicely)to BMW UK HQ and asked if they thought it reasonable that a £60k car (mine has lots of extras!) should idle roughly when the weather was very cold and that it was acceptable for it to do this and what if it caused engine damage eventually? They said they would cover the cost of the parts as a gesture of goodwill but not the labour. I had the levers done but I am not convinced that all is well as I still feel there is a minor misfire on cold start-up. With a V8 it is very difficult to pinpoint one or sometimes even two cylinders misfiring. The US X5 website has loads of posts on this issue (there are more V8s out there and winters are colder than ours - usually!) and some managed to get theirs done under warranty and some had to have them replaced more than once to cure it! I don't think it does any real harm provided one waits until the roughness stops. Many US posters were prepared to live with it rather than forking out £2k. There was mention of a pre-heater available to mainland Europe models - presumably due to cold temperatures in Scandinavia, Alpine regions,etc. It is clearly a very common problem with the Valvetronic V8s.